pjs/editor/libeditor/base/nsEditorUtils.h

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 *
 * The contents of this file are subject to the Netscape Public
 * License Version 1.1 (the "License"); you may not use this file
 * except in compliance with the License. You may obtain a copy of
 * the License at http://www.mozilla.org/NPL/
 *
 * Software distributed under the License is distributed on an "AS
 * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
 * implied. See the License for the specific language governing
 * rights and limitations under the License.
 *
 * The Original Code is mozilla.org code.
 *
 * The Initial Developer of the Original Code is Netscape
 * Communications Corporation.  Portions created by Netscape are
 * Copyright (C) 1998 Netscape Communications Corporation. All
 * Rights Reserved.
 *
 * Contributor(s): 
 */


#ifndef nsEditorUtils_h__
#define nsEditorUtils_h__


#include "nsCOMPtr.h"
#include "nsIDOMNode.h"
#include "nsIDOMSelection.h"
#include "nsIEditor.h"
#include "nsIAtom.h"

#include "nsEditor.h"

class nsAutoEditBatch
{
  private:
    nsCOMPtr<nsIEditor> mEd;
  public:
    nsAutoEditBatch( nsIEditor *aEd) : mEd(do_QueryInterface(aEd)) 
                   { if (mEd) mEd->BeginTransaction(); }
    ~nsAutoEditBatch() { if (mEd) mEd->EndTransaction(); }
};

class nsAutoEditMayBatch
{
  private:
    nsCOMPtr<nsIEditor> mEd;
    PRBool mDidBatch;
  public:
    nsAutoEditMayBatch( nsIEditor *aEd) : mEd(do_QueryInterface(aEd)), mDidBatch(PR_FALSE) {}
    ~nsAutoEditMayBatch() { if (mEd && mDidBatch) mEd->EndTransaction(); }
    
    void batch()  { if (mEd && !mDidBatch) {mEd->BeginTransaction(); mDidBatch=PR_TRUE;} }
};

class nsAutoPlaceHolderBatch
{
  private:
    nsCOMPtr<nsIEditor> mEd;
  public:
    nsAutoPlaceHolderBatch( nsIEditor *aEd, nsIAtom *atom) : mEd(do_QueryInterface(aEd)) 
                   { if (mEd) mEd->BeginPlaceHolderTransaction(atom); }
    ~nsAutoPlaceHolderBatch() { if (mEd) mEd->EndPlaceHolderTransaction(); }
};


class nsAutoSelectionReset
{
  private:
    /** ref-counted reference to the selection that we are supposed to restore */
    nsCOMPtr<nsIDOMSelection> mSel;

    /** PR_TRUE if this instance initialized itself correctly */
    PRBool mInitialized;

    nsCOMPtr<nsIDOMNode> mStartNode;
    nsCOMPtr<nsIDOMNode> mEndNode;
    PRInt32 mStartOffset;
    PRInt32 mEndOffset;

  public:
    /** constructor responsible for remembering all state needed to restore aSel */
    nsAutoSelectionReset(nsIDOMSelection *aSel);
    
    /** destructor restores mSel to its former state */
    ~nsAutoSelectionReset();
};

/***************************************************************************
 * stack based helper class for StartOperation()/EndOperation() sandwich
 */
class nsAutoRules
{
  public:
  
  nsAutoRules(nsEditor *ed, PRInt32 action, nsIEditor::EDirection aDirection) : 
         mEd(ed), mAction(action), mDirection(aDirection)
                {if (mEd) mEd->StartOperation(mAction, mDirection);}
  ~nsAutoRules() {if (mEd) mEd->EndOperation(mAction, mDirection);}
  
  protected:
  nsEditor *mEd;
  PRInt32 mAction;
  nsIEditor::EDirection mDirection;
};



#endif // nsEditorUtils_h__